What are the main categories of systematic trading strategies (e.g. momentum, mean reversion), as might be considered by an index or fund-of-fund analyst?
Are there any common sub-strategies?
There are other strategy types not covered by mean-reversion/trend following:
There is no official taxonomy of quant trading models. After all, "valuations" are inherently subjective, no matter how much math we put behind them. But there are some industry-standard terms that might be helpful.
Inside the Black Box has the following break-down:
It's also possible to break-down by implementation:
And these don't even get into portfolio construction, position limits, risk monitoring, etc.
As for what works, keep this maxim in mind:
And lastly, comparing chartists to quants is like comparing astrologists to astronomers.